Low-temperature preparation of nanostructured Li2TiO3 tritium breeder ceramic pebbles using CTAB-modified ultrafine powders by a mixed solvent-thermal method

Abstract Effects of cetyl trimethyl ammonium bromide (CTAB) on the formation of Li2TiO3 nanocrystals during ethanol-water solvothermal reactions were investigated. Addition of CTAB changed Li2TiO3 crystalline morphology from large to small aggregate particles due to the steric repulsion and electrostatic interaction of the CTAB ligands. Aggregate particle size of the Li2TiO3 precursor was reduced from 455.2 to 138.7 nm by preventing their agglomeration after CTAB addition. This was followed by sintering the green body prepared with the CTAB-modified precursor powders using an indirect wet method, then the nanostructured Li2TiO3 ceramic pebbles were obtained at relatively low temperatures from 750 to 800 °C for 4 h. Nanostructured Li2TiO3 ceramic pebbles had small grains and a large number of grain boundaries, which might potentially improve the radiation tolerance, tritium release rate, and mechanical properties of Li2TiO3 tritium breeder pebbles. In addition, grain growth mechanisms as function of different sintering temperatures, crush load as well as relative density of fabricated nanostructured Li2TiO3 ceramic pebbles were also investigated.